tests/test-dirstate-status-write-race.t
branchstable
changeset 50215 ae61851e6fe2
child 50216 02bf2f94a04c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/test-dirstate-status-write-race.t	Tue Feb 28 15:25:47 2023 +0100
@@ -0,0 +1,190 @@
+=====================================================================
+Check potential race conditions between a status and other operations
+=====================================================================
+
+The `hg status` command can run without the wlock, however it might end up
+having to update the on-disk dirstate files, for example to mark ambiguous
+files as clean, or to update directory caches information with dirstate-v2.
+
+
+If another process updates the dirstate in the meantime we might run into
+trouble. Especially, commands doing semantic changes like `hg add` or
+ `hg commit` should not see their update erased by a concurrent status.
+
+Unlike commands like `add` or `commit`, `status` only writes the dirstate
+to update caches, no actual information is lost if we fail to write to disk.
+
+
+This test file is meant to test various cases where such parallel operations
+between a status with reasons to update the dirstate and another semantic
+changes happen.
+
+
+Setup
+=====
+
+  $ directories="dir dir/nested dir2"
+  $ first_files="dir/nested/a dir/b dir/c dir/d dir2/e f"
+  $ second_files="g dir/nested/h dir/i dir/j dir2/k dir2/l dir/nested/m"
+  $ extra_files="dir/n dir/o p q"
+
+  $ hg init reference-repo
+  $ cd reference-repo
+  $ mkdir -p dir/nested dir2
+  $ touch -t 200001010000 $first_files $directories
+  $ hg commit -Aqm "recreate a bunch of files to facilitate dirstate-v2 append"
+  $ touch -t 200001010010 $second_files $directories
+  $ hg commit -Aqm "more files to have two commits"
+  $ hg log -G -v
+  @  changeset:   1:c349430a1631
+  |  tag:         tip
+  |  user:        test
+  |  date:        Thu Jan 01 00:00:00 1970 +0000
+  |  files:       dir/i dir/j dir/nested/h dir/nested/m dir2/k dir2/l g
+  |  description:
+  |  more files to have two commits
+  |
+  |
+  o  changeset:   0:4f23db756b09
+     user:        test
+     date:        Thu Jan 01 00:00:00 1970 +0000
+     files:       dir/b dir/c dir/d dir/nested/a dir2/e f
+     description:
+     recreate a bunch of files to facilitate dirstate-v2 append
+  
+  
+  $ hg manifest
+  dir/b
+  dir/c
+  dir/d
+  dir/i
+  dir/j
+  dir/nested/a
+  dir/nested/h
+  dir/nested/m
+  dir2/e
+  dir2/k
+  dir2/l
+  f
+  g
+
+Add some unknown files and refresh the dirstate
+
+  $ touch -t 200001010020 $extra_files
+  $ hg add dir/o
+  $ hg remove dir/nested/m
+
+  $ hg st
+  A dir/o
+  R dir/nested/m
+  ? dir/n
+  ? p
+  ? q
+  $ hg debugstate
+  n 644          0 2000-01-01 00:00:00 dir/b
+  n 644          0 2000-01-01 00:00:00 dir/c
+  n 644          0 2000-01-01 00:00:00 dir/d
+  n 644          0 2000-01-01 00:10:00 dir/i
+  n 644          0 2000-01-01 00:10:00 dir/j
+  n 644          0 2000-01-01 00:00:00 dir/nested/a
+  n 644          0 2000-01-01 00:10:00 dir/nested/h
+  r ?????????????????????????????????? dir/nested/m (glob)
+  a ?????????????????????????????????? dir/o (glob)
+  n 644          0 2000-01-01 00:00:00 dir2/e
+  n 644          0 2000-01-01 00:10:00 dir2/k
+  n 644          0 2000-01-01 00:10:00 dir2/l
+  n 644          0 2000-01-01 00:00:00 f
+  n 644          0 2000-01-01 00:10:00 g
+  $ hg debugstate > ../reference
+  $ cd ..
+
+Explain / verify the test principles
+------------------------------------
+
+First, we can properly copy the reference
+
+  $ cp -a reference-repo sanity-check
+  $ cd sanity-check
+  $ hg debugstate
+  n 644          0 2000-01-01 00:00:00 dir/b
+  n 644          0 2000-01-01 00:00:00 dir/c
+  n 644          0 2000-01-01 00:00:00 dir/d
+  n 644          0 2000-01-01 00:10:00 dir/i
+  n 644          0 2000-01-01 00:10:00 dir/j
+  n 644          0 2000-01-01 00:00:00 dir/nested/a
+  n 644          0 2000-01-01 00:10:00 dir/nested/h
+  r ?????????????????????????????????? dir/nested/m (glob)
+  a ?????????????????????????????????? dir/o (glob)
+  n 644          0 2000-01-01 00:00:00 dir2/e
+  n 644          0 2000-01-01 00:10:00 dir2/k
+  n 644          0 2000-01-01 00:10:00 dir2/l
+  n 644          0 2000-01-01 00:00:00 f
+  n 644          0 2000-01-01 00:10:00 g
+  $ hg debugstate > ../post-copy
+  $ diff ../reference ../post-copy
+
+And status thinks the cache is in a proper state
+
+  $ hg st
+  A dir/o
+  R dir/nested/m
+  ? dir/n
+  ? p
+  ? q
+  $ hg debugstate
+  n 644          0 2000-01-01 00:00:00 dir/b
+  n 644          0 2000-01-01 00:00:00 dir/c
+  n 644          0 2000-01-01 00:00:00 dir/d
+  n 644          0 2000-01-01 00:10:00 dir/i
+  n 644          0 2000-01-01 00:10:00 dir/j
+  n 644          0 2000-01-01 00:00:00 dir/nested/a
+  n 644          0 2000-01-01 00:10:00 dir/nested/h
+  r ?????????????????????????????????? dir/nested/m (glob)
+  a ?????????????????????????????????? dir/o (glob)
+  n 644          0 2000-01-01 00:00:00 dir2/e
+  n 644          0 2000-01-01 00:10:00 dir2/k
+  n 644          0 2000-01-01 00:10:00 dir2/l
+  n 644          0 2000-01-01 00:00:00 f
+  n 644          0 2000-01-01 00:10:00 g
+  $ hg debugstate > ../post-status
+  $ diff ../reference ../post-status
+
+Then we can start a status that:
+- has some update to do (the touch call)
+- will wait AFTER running status, but before updating the cache on disk
+
+  $ touch -t 200001010001 dir/c
+  $ hg st >$TESTTMP/status-race-lock.out 2>$TESTTMP/status-race-lock.log \
+  > --config rhg.on-unsupported=abort \
+  > --config devel.sync.status.pre-dirstate-write-file=$TESTTMP/status-race-lock \
+  > &
+  $ $RUNTESTDIR/testlib/wait-on-file 5 $TESTTMP/status-race-lock.waiting
+
+We check it runs the status first by modifying a file and updating another timestamp
+
+  $ touch -t 200001010003 dir/i
+  $ echo babar > dir/j
+  $ touch $TESTTMP/status-race-lock
+  $ wait
+
+The test process should have reported a status before the change we made,
+and should have missed the timestamp update
+
+  $ cat $TESTTMP/status-race-lock.out
+  A dir/o
+  R dir/nested/m
+  ? dir/n
+  ? p
+  ? q
+  $ cat $TESTTMP/status-race-lock.log
+  $ hg debugstate | grep dir/c
+  n 644          0 2000-01-01 00:01:00 dir/c
+  $ hg debugstate | grep dir/i
+  n 644          0 2000-01-01 00:10:00 dir/i
+  $ hg debugstate | grep dir/j
+  n 644          0 2000-01-01 00:10:00 dir/j
+
+final cleanup
+
+  $ rm $TESTTMP/status-race-lock $TESTTMP/status-race-lock.waiting
+  $ cd ..